Method and apparatus of electrophoretic deposition

ABSTRACT

A method of electrophoretic deposition includes: providing an electrophoresis tank, an anode substrate, and a cathode substrate; disposing the anode substrate and the cathode substrate oppositely in the electrophoresis tank; adjusting relative positions of the cathode substrate and the anode substrate for varying each of the distances between corresponding regions on the cathode substrate and the anode substrate; and inputting cathode voltage and anode voltage respectively to a cathode electrode of the cathode substrate and a anode electrode of the anode substrate for performing the electrophoretic deposition.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and an apparatus ofelectrophoretic deposition, and more particularly, to a method and anapparatus of electrophoretic deposition improving the uniformity of theelectrophoretic deposition while a voltage distribution of electrodes isnon-uniform.

2. Description of the Prior Art

Electrophoresis is a reaction that charged particles in anelectrophoresis buffer may move toward two electrode substrates withopposite charges under an effect of an electric field. Materials carriedby the charged particles may gather on the electrode substrate forforming a coating layer in the electrophoresis buffer called anelectrophoretic deposition.

The electrophoretic deposition may be employed for depositing coatingmaterials, metal oxides, and fluorescent powders. In recent years,related technologies and applications of carbon nanotubes (CNT) havebeen rapidly developed, and the electrophoretic deposition also has beenemployed for depositing CNT films. Electrophoresis in theelectrophoresis buffer is driven by the electrical field between twoelectrodes. Uniformity of the electrophoretic deposition may bedifficult to control because the voltage drop issue on the electrode maybe serious, especially when the pattern of the electrode is linear orwhen the area of the electrode is enlarged. The voltage distribution ofdifferent regions on the electrode may become non-uniform, and theuniformity of the electrophoretic deposition may be therefore affected.Display quality and manufacturing yield of a display device, such as alarge-sized display device, may be affected when the electrophoreticdeposition is employed for forming material layers in the displaydevice.

SUMMARY OF THE INVENTION

It is one of the objectives of the present invention to provide a methodand an apparatus of electrophoretic deposition for improving thenon-uniform distribution of voltage caused by the shape and the size ofthe electrodes and the uniformity of the electrophoretic deposition maythen be enhanced.

To achieve the purposes described above, a preferred embodiment of thepresent invention provides a method of electrophoretic deposition. Themethod of the electrophoretic deposition includes the following steps.First, an electrophoresis tank, an anode substrate, and a cathodesubstrate are provided. The electrophoresis tank contains anelectrophoresis buffer. The anode substrate includes at least one anodeelectrode, and the cathode substrate includes at least one cathodeelectrode. The anode substrate and the cathode substrate are thendisposed in the electrophoresis buffer, and the anode substrate and thecathode substrate are disposed oppositely in the electrophoresis tank.Relative positions of the cathode substrate and the anode substrate areadjusted for varying each of the distances between corresponding regionson the cathode substrate and the anode substrate. Cathode voltage andanode voltage are inputted respectively to the cathode electrode of thecathode substrate and to the anode electrode of the anode substrate forperforming the electrophoretic deposition.

To achieve the purposes described above, another preferred embodiment ofthe present invention provides a method of electrophoretic deposition.The method of the electrophoretic deposition includes the followingsteps. First, an electrophoresis tank, an anode substrate, and a cathodesubstrate are provided. The electrophoresis tank contains anelectrophoresis buffer. The anode substrate includes a plurality ofanode electrodes, and the cathode substrate includes at least onecathode electrode. The anode substrate and the cathode substrate arethen disposed in the electrophoresis buffer, and the anode substrate andthe cathode substrate are disposed oppositely and parallel to each otherin the electrophoresis tank. Cathode voltage is inputted to the cathodeelectrode of the cathode substrate, and anode voltage with differentvalues is inputted respectively to each of the anode electrodes of theanode substrate for performing the electrophoretic deposition.

To achieve the purposes described above, a preferred embodiment of thepresent invention provides an apparatus of electrophoretic deposition.The apparatus of the electrophoretic deposition includes a power supply,an electrophoresis tank, a cathode substrate, and an anode substrate.The power supply includes an anode terminal and a cathode terminal. Theelectrophoresis tank is used to contain an electrophoresis buffer. Thecathode substrate is disposed in the electrophoresis tank. The cathodesubstrate includes at least one cathode electrode electrically connectedto the cathode terminal of the power supply. The anode substrate isdisposed correspondingly to the cathode substrate in the electrophoresistank. The anode substrate includes at least one anode electrodeelectrically connected to the anode terminal of the power supply. Theanode substrate is disposed tiltedly toward the cathode substrate, and adistance between one region on the anode substrate and a correspondingregion on the cathode substrate is different from a distance betweenanother region on the anode substrate and another corresponding regionon the cathode substrate.

To achieve the purposes described above, another preferred embodiment ofthe present invention provides an apparatus of electrophoreticdeposition. The apparatus of the electrophoretic deposition includes apower supply, an electrophoresis tank, a cathode substrate, and an anodesubstrate. The power supply includes a plurality of anode terminals anda cathode terminal. The electrophoresis tank is used to contain anelectrophoresis buffer. The cathode substrate is disposed in theelectrophoresis tank. The cathode substrate includes at least onecathode electrode electrically connected to the cathode terminal of thepower supply. The anode substrate is disposed parallel to the cathodesubstrate in the electrophoresis tank. The anode substrate includes aplurality of anode electrodes electrically connected to the anodeterminals of the power supply respectively. Each of the anode terminalsis employed for providing anode voltage with different values to each ofthe anode electrodes, and the cathode terminal is employed for providingcathode voltage to the cathode electrode.

In the present invention, the distances between regions on two electrodesubstrates may be adjusted and a plurality of anode electrodes may beemployed for compensating the voltage drop issue on the cathodesubstrate. The problem caused by the non-uniform distribution of voltageon the cathode substrate due to the effect of the voltage drop may beimproved, and the uniformity of the electrophoretic deposition rate maythen be enhanced.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view diagram illustrating an apparatus ofelectrophoretic deposition according to a preferred embodiment of thepresent invention.

FIG. 2 is a stereoscopic view diagram illustrating an apparatus ofelectrophoretic deposition according to a preferred embodiment of thepresent invention.

FIG. 3 is a schematic diagram illustrating a cathode substrate of anapparatus of electrophoretic deposition according to another preferredembodiment of the present invention.

FIG. 4 is a cross-sectional view diagram illustrating an apparatus ofelectrophoretic deposition according to further another preferredembodiment of the present invention.

FIG. 5 is a stereoscopic view diagram illustrating an apparatus ofelectrophoretic deposition according to further another preferredembodiment of the present invention.

FIG. 6 is a schematic diagram illustrating an anode substrate of anapparatus of electrophoretic deposition according to further anotherpreferred embodiment of the present invention.

DETAILED DESCRIPTION

Certain terms are used throughout the description and following claimsto refer to particular components. As one skilled in the art willunderstand, electronic equipment manufacturers may refer to a componentby different names. This document does not intend to distinguish betweencomponents that differ in name but not function. In the followingdescription and in the claims, the terms “include” and “include” areused in an open-ended fashion, and thus should be interpreted to mean“include, but not limited to . . . . ” In addition, to simplify thedescriptions and make it more convenient to compare between eachembodiment, identical components are marked with the same referencenumerals in each of the following embodiments. Please note that thefigures are only for illustration and the figures may not be to scale.

Please refer to FIG. 1 and FIG. 2. FIG. 1 is a cross-sectional viewdiagram illustrating an apparatus of electrophoretic depositionaccording to a preferred embodiment of the present invention. FIG. 2 isa stereoscopic view diagram illustrating the apparatus of theelectrophoretic deposition according to the preferred embodiment of thepresent invention. As shown in FIG. 1 and FIG. 2, in this embodiment, anapparatus of electrophoretic deposition 10 includes a power supply 11,an electrophoresis tank 12T, a cathode substrate 14, and an anodesubstrate 13. The power supply 11 includes an anode terminal 11A and acathode terminal 11C. The electrophoresis tank 12T is used to contain anelectrophoresis buffer 12. The cathode substrate 14 is disposed in theelectrophoresis tank 12T. The cathode substrate 14 includes at least onecathode electrode 16 electrically connected to the cathode terminal 11Cof the power supply 11. In this embodiment, the cathode substrate 14includes a plurality of cathode electrodes 16, but the present inventionis not limited to this and the cathode substrate 14 may include only onecathode electrode 16.

The cathode substrate 14 may have a first cathode region 14Z1 and asecond cathode region 14ZX. Each of the cathode electrodes 16 within thefirst cathode region 14Z1 is electrically connected to the cathodeterminal 11C of the power supply 11, and voltage VCZX of each thecathode electrodes 16 within the second cathode region 14ZX is lowerthan voltage VCZ1 of each the cathode electrodes 16 within the firstcathode region 14Z1 due to an effect of voltage drop on the cathodeelectrodes 16.

The anode substrate 13 is disposed correspondingly to the cathodesubstrate 14 in the electrophoresis tank 12T. The anode substrate 13includes at least one anode electrode 15. In this embodiment, the anodeelectrode 15 may include a pattern such as a rectangular pattern with anarea nearly equal to a surface of the anode substrate 13, but thepresent invention is not limited to this and the anode electrode 15 mayinclude other appropriate patterns. As shown in FIG. 1, in thisembodiment, the anode substrate 13 is disposed tiltedly toward thecathode substrate 14, and a distance between one region on the anodesubstrate 13 and a corresponding region on the cathode substrate 14 isdifferent from a distance between another region on the anode substrate13 and another corresponding region on the cathode substrate 14. Theanode substrate 13 may have a first anode region 13Z1 corresponding tothe first cathode region 14Z1 of the cathode substrate 14, and the anodesubstrate 13 may have a second anode region 13ZX corresponding to thesecond cathode region 14ZX of the cathode substrate 14. The anodeelectrode 15 within the first anode region 13Z1 is electricallyconnected to the anode terminal 11A of the power supply 11. A firstelectrophoretic deposition rate RZ1 generated between the first anoderegion 13Z1 and the first cathode region 14Z1 may be equal to a secondelectrophoretic deposition rate RZX generated between the second anoderegion 13ZX and the second cathode region 14ZX, and a distance DZ1between the first anode region 13Z1 and the first cathode region 14Z1may be larger than a distance DZX between the second anode region 13ZXand the second cathode region 14ZX.

It is worth noticing that, in this embodiment, the voltage VCZX of thecathode electrodes 16 within the second cathode region 14ZX, which isaway from the region connected to the power supply 11, may be affectedmore seriously by the voltage drop issue caused by properties such asshape and resistivity of the cathode electrode 16. The voltage VCZX ofthe cathode electrode 16 within the second cathode region 14ZX maytherefore become lower than the voltage VCZ1 of the cathode electrode 16within the first cathode region 14Z1. The distance DZX between thesecond anode region 13ZX and the second cathode region 14ZX may bereduced, and the distance DZ1 between the first anode region 13Z1 andthe first cathode region 14Z1 may become larger than the distance DZXbetween the second anode region 13ZX and the second cathode region 14ZXfor compensating the influence of the voltage VCZX which is lower thanthe voltage VCZ1.

The first electrophoretic deposition rate RZ1 generated between thefirst anode region 13Z1 and the first cathode region 14Z1 may thereforebecome equal to the second electrophoretic deposition rate RZX generatedbetween the second anode region 13ZX and the second cathode region 14ZX.Additionally, in this embodiment, main components of the electrophoresisbuffer 12 may include carbon nanotubes, fluorescent powders, or metaloxides such as lanthanum strontium manganite (LSM), cerium gadoliniumoxide (CGO), yttria-stabilized zirconia (YSZ) and lanthanum strontiumgallium magnesium oxide (LSGM), but not limited thereto. Theelectrophoresis buffer 12 may further include solvents, dispersingagents, or salts such as sodium nitrite magnesium nitrite, yttriumnitrite, or aluminium nitrite, but the electrophoresis buffer 12 of thisinvention is not limited to this and may include other necessarycomponents. In addition, materials of the anode electrodes 15 and thecathode electrode 16 may include conductive metals, transparentconductive materials or other appropriate conductive materials. Theconductive materials may include aluminum, chromium, molybdenum,titanium, copper, silver, or alloys of these materials. The transparentconductive materials may include indium tin oxide (ITO), indium zincoxide (IZO), aluminum zinc oxide (AZO) or other transparent conductivematerials.

As shown in FIG. 2, in this embodiment, the cathode substrate 14 mayinclude a plurality of stripe cathode electrodes 16, but the cathodesubstrate 14 of the present invention is not limited to this and mayinclude only one cathode electrode or the cathode electrodes with otherappearances. Please refer to FIG. 3. FIG. 3 is a schematic diagramillustrating a cathode substrate of an apparatus of electrophoreticdeposition according to another preferred embodiment of the presentinvention. As shown in FIG. 3, the cathode substrate 14 may include acathode electrode 17, and the cathode electrode 17 may be an “S”-shapedpattern meandering over the cathode substrate 14. Except for the cathodeelectrode 17, the apparatus of the electrophoretic deposition of thisembodiment is similar to the apparatus of the electrophoretic deposition10 mentioned above and will not be redundantly described.

Please refer to FIG. 1 and FIG. 2 again. As shown in FIG. 1 and FIG. 2,a preferred embodiment of the present invention provides a method ofelectrophoretic deposition. The method of the electrophoretic depositionincludes the following steps. First, the apparatus of theelectrophoretic deposition 10 mentioned above is provided. The anodesubstrate 13 and the cathode substrate 14 are disposed in theelectrophoresis buffer 12. Relative positions of the cathode substrate14 and the anode substrate 13 are then adjusted for varying each of thedistances between corresponding regions on the cathode substrate 14 andthe anode substrate 13. Subsequently, cathode voltage and anode voltageare inputted respectively to the cathode electrode 16 of the cathodesubstrate 14 and to the anode electrode 15 of the anode substrate 13 forperforming the electrophoretic deposition.

In this embodiment, voltage VCZ1 exists on the cathode electrodes 16within the first cathode region 14Z1, voltage VCZX exists on the cathodeelectrodes 16 within the second cathode region 14ZX, voltage VAZ1 existson the anode electrode 15 within the first anode region 13Z1, andvoltage VAZX exists on the anode electrode 15 within the second anoderegion 13ZX. The voltage VCZX of the cathode electrodes 16 within thesecond cathode region 14ZX is lower than the voltage VCZ1 of the cathodeelectrodes 16 within the first cathode region 14Z1 because of thevoltage drop issue on the cathode electrodes 16.

In this embodiment, the anode electrode 15 may be a rectangular patternwith an area nearly equal to a surface of the anode substrate 13, andthen the voltage VAZ1 of the anode electrode 15 within the first anoderegion 13Z1 may be equal to the voltage VAZX of the anode electrode 15within the second anode region 13ZX, but the voltage VAZX of thisinvention is not limited to this and may be different from the voltageVAZ1. It is worth noticing that, in this embodiment, the voltage VCZX ofthe cathode electrodes 16 within the second cathode region 14ZX, whichis away from the region connected to the power supply 11, may beaffected more seriously by the voltage drop issue especially when eachof the cathode electrodes 16 is a linear electrode with high aspectratio or the cathode electrodes 16 include high resistivity materials.The voltage VCZX of the cathode electrode 16 within the second cathoderegion 14ZX may therefore become lower than the voltage VCZ1 of thecathode electrode 16 within the first cathode region 14Z1.

In this embodiment, the anode substrate 13 is disposed tiltedly towardthe cathode substrate 14, and the distance DZ1 between the first anoderegion 13Z1 and the first cathode region 14Z1 may become larger than thedistance DZX between the second anode region 13ZX and the second cathoderegion 14ZX for compensating the influence of the voltage VCZX on thesecond electrophoretic deposition rate RZX generated between the secondanode region 13ZX and the second cathode region 14ZX. Additionally, inother embodiments of the present invention, the positions and tiltedangles of the anode substrate 13 and the cathode substrate 14 may befurther modified in the electrophoresis buffer 12 for improving theuniformity of the deposition rate, which may be influenced by thenon-uniform voltage distribution on the anode substrate 13 and thecathode substrate 14. In addition, the components of the electrophoresisbuffer and the design of the electrodes may be further modified fordepositing materials on the anode electrodes or the cathode electrodesby the electrophoretic deposition.

Please refer to FIGS. 4-6. FIG. 4 is a cross-sectional view diagramillustrating an apparatus of electrophoretic deposition according toanother preferred embodiment of the present invention. FIG. 5 is astereoscopic view diagram illustrating the apparatus of theelectrophoretic deposition in this embodiment. FIG. 6 is a schematicdiagram illustrating an anode substrate of the apparatus of theelectrophoretic deposition in this embodiment. To simplify thedescription, the identical components in each of the embodiments of thisinvention are marked with identical symbols. As shown in FIGS. 4-6, inthis embodiment, an apparatus of electrophoretic deposition 20 includesa power supply 11, an electrophoresis tank 12T, a cathode substrate 14,and an anode substrate 13. The power supply 11 includes a plurality ofanode terminals 11A and a cathode terminal 11C. The electrophoresis tank12T is used to contain an electrophoresis buffer 12. The cathodesubstrate 14 is disposed in the electrophoresis tank 12T. The cathodesubstrate 14 includes at least one cathode electrode 16 electricallyconnected to the cathode terminal 11C of the power supply 11. In thisembodiment, the cathode substrate 14 includes a plurality of cathodeelectrodes 16, but the present invention is not limited to this and thecathode substrate 14 may include only one cathode electrode 16. Inaddition, the cathode substrate 14 may have a first cathode region 14Z1and a second cathode region 14ZX. Each of the cathode electrodes 16within the first cathode region 14Z1 is electrically connected to thecathode terminal 11C of the power supply 11, and voltage VCZX of eachthe cathode electrodes 16 within the second cathode region 14ZX is lowerthan voltage VCZ1 of each the cathode electrodes 16 within the firstcathode region 14Z1 due to an effect of voltage drop on the cathodeelectrodes 16.

The anode substrate 13 is disposed parallel to the cathode substrate 14in the electrophoresis tank 12T. The anode substrate 13 includes aplurality of anode electrodes 18. Each of the anode electrodes 18 iselectrically connected to each of the anode terminals 11A of the powersupply 11 respectively. The anode terminals 11A are employed forproviding anode voltage with different values to each of the anodeelectrodes 18, and the cathode terminal 11C is employed for providingcathode voltage to the cathode electrodes 16. In this embodiment,voltage VAZ1 exists on the anode electrode 18 within a first anoderegion 13Z1, which is corresponding to the first cathode region 14Z1.Voltage VAZX exits on the anode electrode 18 within a second anoderegion 13ZX, which corresponds to the second cathode region 14ZX. Thevoltage VAZ1 of the anode electrode 18 within the first anode region13Z1 is lower than the voltage VAZX of the anode electrode 18 within thesecond anode region 13ZX, and a first electrophoretic deposition rateRZ1 generated between the first anode region 13Z1 and the first cathoderegion 14Z1 may be equal to a second electrophoretic deposition rate RZXgenerated between the second anode region 13ZX and the second cathoderegion 14ZX.

In this embodiment, the appearance of the cathode electrode 16 includesa stripe pattern, and the voltage VCZX of the cathode electrodes 16within the second cathode region 14ZX, which is away from the regionconnected to the power supply 11, may be affected more seriously by thevoltage drop issue caused by properties such as length and resistivityof the cathode electrode 16. The voltage VCZX of the cathode electrode16 within the second cathode region 14ZX may therefore become lower thanthe voltage VCZ1 of the cathode electrode 16 within the first cathoderegion 14Z1. It is worth noticing that, in this embodiment, a pluralityof the anode electrodes 18, which are stripe patterns and disposedparallel to each other, are electrically connected to the anodeterminals 11A of the power supply 11, and voltage with different valuesmay exist on different regions of the anode substrate 13. The voltageVAZ1 of the anode electrode 18 within the first anode region 13Z1 maythen be lower than the voltage VAZX of the anode electrode 18 within thesecond anode region 13ZX. In other words, in this embodiment, the anodevoltage with different values may be provided to each of the anodeelectrodes 18, and the voltage existing on the anode electrodes 18 maybe increasing from the top of the anode substrate 13 to the bottom ofthe anode substrate 13 for compensating the voltage drop issue ondifferent regions of the cathode substrate 14, but the present inventionis not limited to this and the voltage on each of the regions of theanode substrate 13 may be modified for compensating the voltage dropissue on the different regions of the cathode substrate 14. The firstelectrophoretic deposition rate RZ1 generated between the first anoderegion 13Z1 and the first cathode region 14Z1 may then be equal to thesecond electrophoretic deposition rate RZX generated between the secondanode region 13ZX and the second cathode region 14ZX.

As shown in FIG. 6, each of the anode electrodes 18 of this embodimentare disposed parallel to each other, but the present invention is notlimited to this and other allocation approaches may be applied fortuning the condition of the electrophoretic deposition. For example, inother embodiments of the present invention, the patterns and thepositions of the anode electrodes may be further modified, and thevoltage existing on the anode electrodes may then be different from acenter region of the anode substrate to an outer region of the anodesubstrate for compensating the voltage drop issue on different regionsof the cathode substrate. Additionally, the components and materialproperties of the electrophoresis buffer 12 in this embodiment aresimilar to the embodiment mentioned above and will not be redundantlydescribed.

Please refer to FIGS. 4-6 again. As shown in FIGS. 4-6, anotherpreferred embodiment of the present invention provides a method ofelectrophoretic deposition. The following description will detail thedifferences between the method of the electrophoretic deposition in thisembodiment and the method of the electrophoretic deposition in theabove-mentioned embodiment. In the method of the electrophoreticdeposition of this embodiment, the anode substrate 13 and the cathodesubstrate 14 are disposed oppositely and parallel to each other in theelectrophoresis buffer 12. In other words, the distance DZ1 between thefirst anode region 13Z1 and the first cathode region 14Z1 is equal tothe distance DZX between the second anode region 13ZX and the secondcathode region 14ZX, but not limited thereto. In this embodiment, theanode substrate 13 may include a plurality of anode electrodes 18.

The method of the electrophoretic deposition in this embodiment mayinclude inputting cathode voltage to the cathode electrode 16 of thecathode substrate 14 and inputting anode voltage with different valuesrespectively to each of the anode electrodes 18 of the anode substrate13 for keeping the voltage VAZ1 of the first anode region 13Z1 lowerthan the voltage VAZX of the second anode region 13ZX. Specifically, thevoltage on each regions of the anode substrate 13 may be separatelycontrolled for compensating the voltage drop issue on the cathodesubstrates 14, and the first electrophoretic deposition rate RZ1generated between the first anode region 13Z1 and the first cathoderegion 14Z1 may then be equal to the second electrophoretic depositionrate RZX generated between the second anode region 13ZX and the secondcathode region 14ZX. As shown in FIG. 6, the anode electrodes 18 in thisembodiment are disposed parallel to each other, but the presentinvention is not limited to this and other allocation approaches may beemployed for modifying the process conditions of the electrophoreticdeposition. Additionally, in other embodiments of the present invention,the above-mentioned method of adjusting the distances between regions onthe anode substrate 13 and the cathode substrate 14 may be combined withthe method of tuning the voltage distribution on the anode substrate 13for optimizing the uniformity of the electrophoretic deposition.

To summarize the above descriptions, in the present invention, themethod of adjusting each of the distances between regions on the anodesubstrate and the cathode substrate, and the design of the electrodesmay be employed for improving the issue that the voltage distribution onthe cathode substrate may be non-uniform because of the pattern of thecathode electrode or the material properties of the cathode electrode.The uniformity of the electrophoretic deposition rate may then beeffectively enhanced.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

1. A method of electrophoretic deposition, comprising: providing anelectrophoresis tank containing an electrophoresis buffer; providing ananode substrate and a cathode substrate, wherein the anode substratecomprises at least one anode electrode and the cathode substratecomprises at least one cathode electrode; disposing the anode substrateand the cathode substrate in the electrophoresis buffer, wherein theanode substrate and the cathode substrate are disposed oppositely in theelectrophoresis tank; adjusting relative positions of the cathodesubstrate and the anode substrate for varying each of distances betweencorresponding regions on the cathode substrate and the anode substrate;and inputting cathode voltage and anode voltage respectively to at leastone cathode electrode of the cathode substrate and at least one anodeelectrode of the anode substrate for performing the electrophoreticdeposition.
 2. The method of electrophoretic deposition of claim 1,wherein a first cathode region of the cathode substrate and a firstanode region of the anode substrate are disposed oppositely to eachother, a second cathode region of the cathode substrate and a secondanode region of the anode substrate are disposed oppositely to eachother, voltage of the cathode electrode within the second cathode regionis lower than voltage of the cathode electrode within the first cathoderegion due to an effect of voltage drop, and a distance between thesecond cathode region and the second anode region is smaller than adistance between the first cathode region and the first anode region. 3.A method of electrophoretic deposition, comprising: providing anelectrophoresis tank containing an electrophoresis buffer; providing ananode substrate and a cathode substrate, wherein the anode substratecomprises a plurality of anode electrodes and the cathode substratecomprises at least one cathode electrode; disposing the anode substrateand the cathode substrate in the electrophoresis buffer, wherein theanode substrate and the cathode substrate are disposed oppositely andparallel to each other in the electrophoresis tank; and inputtingcathode voltage to at least one cathode electrode of the cathodesubstrate and inputting anode voltage with different values respectivelyto each of the anode electrodes of the anode substrate for performingthe electrophoretic deposition.
 4. The method of electrophoreticdeposition of claim 3, wherein a first cathode region of the cathodesubstrate and a first anode region of the anode substrate are disposedoppositely to each other, a second cathode region of the cathodesubstrate and a second anode region of the anode substrate are disposedoppositely to each other, voltage of the cathode electrode within thesecond cathode region is lower than voltage of the cathode electrodewithin the first cathode region due to an effect of voltage drop, andvoltage of the anode electrode within the second anode region is higherthan voltage of the anode electrode within the first anode region.
 5. Anapparatus of electrophoretic deposition, comprising: a power supplycomprising an anode terminal and a cathode terminal; an electrophoresistank for containing an electrophoresis buffer; a cathode substratedisposed in the electrophoresis tank, wherein the cathode substratecomprises at least one cathode electrode electrically connected to thecathode terminal of the power supply; and an anode substrate disposedcorrespondingly to the cathode substrate in the electrophoresis tank,the anode substrate comprising at least one anode electrode electricallyconnected to the anode terminal of the power supply, wherein the anodesubstrate is disposed tiltedly toward the cathode substrate, and adistance between one region on the anode substrate and a correspondingregion on the cathode substrate is different from a distance betweenanother region on the anode substrate and another corresponding regionon the cathode substrate.
 6. The apparatus of electrophoretic depositionof claim 5, wherein the cathode substrate has a first cathode regioncorresponding to a first anode region of the anode substrate, thecathode substrate has a second cathode region corresponding to a secondanode region of the anode substrate, voltage of the cathode electrodewithin the second cathode region is lower than voltage of the cathodeelectrode within the first cathode region due to an effect of voltagedrop, and a distance between the second cathode region and the secondanode region is smaller than a distance between the first cathode regionand the first anode region.
 7. An apparatus of electrophoreticdeposition, comprising: a power supply comprising a plurality of anodeterminals and a cathode terminal; an electrophoresis tank for containingan electrophoresis buffer; a cathode substrate disposed in theelectrophoresis tank, wherein the cathode substrate comprises at leastone cathode electrode electrically connected to the cathode terminal ofthe power supply; and an anode substrate disposed parallel to thecathode substrate in the electrophoresis tank, the anode substratecomprising a plurality of anode electrodes electrically connected to theanode terminals of the power supply respectively; wherein each of theanode terminals is employed for providing anode voltage with differentvalues to each of the anode electrodes, and the cathode terminal isemployed for providing cathode voltage to the cathode electrode.
 8. Theapparatus of electrophoretic deposition of claim 7, wherein the cathodesubstrate has a first cathode region corresponding to a first anoderegion of the anode substrate, the cathode substrate has a secondcathode region corresponding to a second anode region of the anodesubstrate, voltage of the cathode electrode within the second cathoderegion is lower than voltage of the cathode electrode within the firstcathode region due to an effect of voltage drop, and voltage of theanode electrode within the second anode region is higher than voltage ofthe anode electrode within the first anode region.
 9. The apparatus ofelectrophoretic deposition of claim 7, wherein the anode electrodes aredisposed parallel to each other.